Pneumatic tubes or ducts have long been used in the transportation of small, uniform solid objects such as hollow cases or canisters for transporting mail within a building. The use of pneumatic tubes or ducts has also been applied to the transport of bags of rubbish. For example, U.S. Pat. No. 3,853,355 Buisson issued Dec. 10, 1974 discloses a system for discharging rubbish through pneumatic ducts. This system is designed for transporting bags of unsorted household waste in which the bags are heavy and irregular and sometimes leaking sticky substances, so the main problem to be overcome by that system was to provide sufficient momentum to transport the bags of rubbish to the central destruction facility. This was done by having the bag of rubbish travel downwardly, then horizontally and using a secondary fan to first suck air from the tube ahead of the bag and then blow behind the bag. Another pneumatic system for transporting rubbish is disclosed in U.S. Pat. No. 4,995,765 Tokuhiro et al. issued Feb. 26, 1991. Again the units to be transported in this system relate to unsorted household waste which is relatively heavy, and the system involves the containers dropping vertically and then being forced horizontally to the collection area.
Currently, supermarkets collect recycled waste such as aluminum cans which require transportation from the front of the store, where the customers deposit the cans, to the rear of the store where collection vehicles can pick up the materials for recycling. It is undesirable to transport such beverage cans for recycling at ground level through the supermarket at floor level since the materials may leak liquids causing an unsanitary and unsightly situation. Consequently there is a need for a system to transport bags of recycled aluminum cans and the like above the floor level of supermarkets and back down at the rear of the supermarket for collection.